As another election year draws to a close, it’s time again for me to pick the cycle’s winners and losers, my most and least favorite candidates, and those who distinguished themselves by skill or by old-fashioned dumb luck.

After three successive partisan wave elections, the overarching takeaway from the 2012 cycle is that candidates and the campaigns they run still matter. Up and down the ballot — from the presidential race to Senate contests to various House races — we saw examples of how the strength of one candidate/campaign (or the sheer ineptitude of another) made the difference on Election Day.

Given this was a crazy year, it shouldn’t come as a complete surprise that it will take me two columns to run through the various categories and the politicians who deserve mention in each, in addition to my winners.

So, without further delay, here is Part I of this year’s Rothenberg End-of-the-Year Awards for 2012.

Luckiest Candidate of 2012

There are a handful of obvious candidates. Missouri Sen. Claire McCaskill had no chance of winning a second term — until Republican challenger Rep. Todd Akin popularized the term “legitimate rape.” Akin could have spent the entire general election in Finland and beaten McCaskill, and even after his self-inflicted injury, he could have resurrected GOP chances of winning the seat by dropping out. McCaskill is lucky he didn’t.

Similarly, Indiana Democratic Rep. Joe Donnelly had little or no chance of getting elected to the Senate this year — until Richard Mourdock made yet another campaign error, in answering a question about rape and abortion. Donnelly ran a good race, but he wouldn’t have defeated Sen. Richard G. Lugar or any minimally appealing mainstream Republican.

Republican Kerry Bentivolio looked to be merely a humorous anecdote when he entered the GOP primary against then-Rep. Thaddeus McCotter in Michigan’s 11th District. But when McCotter’s staffers failed to collect enough signatures to get the congressman on the ballot, the quirky Bentivolio became the GOP nominee. And now, in an example of the saying that it’s better to be lucky than good, he’s headed to Congress.

But my choice for the Luckiest Politician of 2012 Award this year is Sen. Bill Nelson.

The Florida Democrat won re-election last month by beating GOP Rep. Connie Mack, who raised little money and apparently figured that oozing cockiness was the best way to woo reporters and voters.

But what makes Nelson so lucky is that Mack was the third consecutive mediocre Republican he faced. The Democrat first won his Senate seat by defeating former Rep. Bill McCollum in 2000, and then was blessed with the controversial Katherine Harris as his opponent in 2006.

We can only wonder what sort of damaged candidate the Republicans are planning to nominate there in 2018.

The Best Campaign/Candidate of 2012

There were a lot of excellent campaigns and strong candidates this cycle. It is hard not to include Montana Democratic Sen. Jon Tester on the list. Illinois Republican Rep. Robert Dold lost his bid for re-election but ran a great race. Utah Democratic Rep. Jim Matheson did the impossible by beating strong challenger Mia Love when GOP presidential nominee Mitt Romney was winning his district overwhelmingly.

But for my money, the choice comes down to two Democrats: Georgia Rep. John Barrow and North Dakota Senate hopeful Heidi Heitkamp, who was the favorite of many Twitter followers to win this category.

Barrow certainly had some of the best TV ads of the cycle, and he won by a surprising 7 points in a very difficult district. But he benefited from having the inept Lee Anderson as his GOP opponent, giving him an advantage that others did not have.

For that reason, my winner is Heitkamp, whose strong personal appeal and quality campaign overcame a Republican state wave and an established Republican statewide politician.

The Biggest Upset of 2012

Many readers and Twitter followers think Heitkamp is an easy winner for this category, too, but there were also votes for other excellent choices, including somebody named David A. Curson of Michigan (yes, I know who he is, sort of), incoming GOP Sens. Deb Fischer of Nebraska and Ted Cruz of Texas, Kentucky Republican Rep.-elect Garland “Andy” Barr IV and Matheson.

How you answer this depends on where you start. I’ll focus on my surprise of election night, so my choice is easy: Massachusetts Rep. John F. Tierney’s re-election.

By the time Nov. 6 rolled around, the Democrat looked to me like a dead duck in the face of a personable, pro-abortion-rights, unusually strong Republican challenger Richard Tisei.

The legal problems that engulfed Tierney’s wife and her family looked politically fatal to the congressman, especially after both Republican and Democratic operatives and strategists started telling me privately that the race was over.

But Tierney squeaked by Tisei in a race that had me checking and rechecking my computer on election night, and that is why he is my choice.

Worst Personal Financial Investment By a Candidate

Most candidates put a few dollars into their own campaigns, if only to show a personal commitment to their race. But some candidates make a much larger investment. When the candidates win, their investments look good. When they don’t, those investments look bad, sometimes very bad.

Among the worst “investments” this cycle were those made by Arizona GOP Senate primary loser Wil Cardon, Pennsylvania GOP Senate nominee Tom Smith and unsuccessful Republican Texas Senate primary candidate David Dewhurst. Of the three, only Smith had a competitive general election in which to spend.

But the person who, once again, made the worst investment in her own campaign was Connecticut GOP Senate hopeful Linda McMahon, who contributed $677,000 and loaned her campaign more than $39.3 million as of her Oct. 17 FEC report.

McMahon may well be a wizard when it comes to running an entertainment company, but I wouldn’t ask her for advice about which campaigns to invest in next cycle.

And because her campaign apparently bounced a few checks after the election, I’m not sure I’d lend her any money, either.